Transfer printing methods include: a melting type transfer printing method in which ink including wax, a thermosoftening binder such as resin and a pigment is used; a rubber print type transfer printing method in which plastisol ink including powder of polyvinyl chloride or the like, a plasticizer, and a pigment is used; and a sublimation-type textile printing transfer method in which a thermally subliming dye is used.
Conventionally, various printing plates and printing machines designed for the printing plates have been required for forming transfer printing sheets. In recent years, transfer printing sheets for an inkjet recording method suited to a small lot have been proposed, so that the demand for a sublimation-type textile printing transfer method suited to a small lot has been increasing.
The sublimation-type textile printing transfer method is a method in which a laminate of sublimation-type inkjet textile printing transfer paper and a fabric such as polyester that is a transfer target object is brought into close contact with a heating dryer to thermally sublimate printing ink on the sublimation-type inkjet textile printing transfer paper, thereby performing transfer printing on the transfer target object. The sublimation-type textile printing transfer method has an advantage in that printing of a sharp design that is difficult with the other transfer methods is enabled without impairing the feel and texture of the textile-printed object.
Patent Literature 1 and 2 each discloses sublimation-type inkjet textile printing transfer paper in which an ink receiving layer containing a pigment such as silica and a binder such as polyvinyl alcohol, etc. is provided on a base material, as the sublimation-type inkjet textile printing transfer paper for the inkjet recording method.
In addition, Patent Literature 3 discloses sublimation-type inkjet textile printing transfer paper including an ink receiving layer containing inorganic particles such as porous inorganic fine particles for improving retention of sublimation-type textile printing ink at the ink receiving layer.
However, in these conventional sublimation-type inkjet textile printing transfer papers, when inkjet printing is performed, sublimation-type textile printing ink passes through a coating layer and reaches a base paper layer as a result of placing importance on the absorbability and dryability of the ink. Thus, there is a problem that, when transfer printing is performed onto a transfer target object, the sublimation-type textile printing ink strikes through to the back side different from the ink receiving layer of the transfer paper, or passes through (strikes through) a fabric or the like that is the transfer target object, and adheres to a pressing machine for transfer, or the like.
Since the absorbability and dryability of the sublimation-type textile printing ink and prevention of strike-through of the sublimation-type textile printing ink contradict each other, it is difficult to produce transfer paper that achieves both of these characteristics, that is, sublimation-type inkjet textile printing transfer paper that immediately absorbs/dries the sublimation-type textile printing ink at the time of printing and that prevents strike-through of the sublimation-type textile printing ink at the time of transfer. Furthermore, for the sublimation-type inkjet textile printing transfer paper, the efficiency of transfer onto the transfer target object, such as the reproducibility of an image, the resolution of a transferred image, the density level of the transferred image, and the uniformity of these, is required at a higher level.
In addition, recent sublimation-type textile printing ink itself has been significantly improved in terms of dryability, and thus the necessity of porous inorganic fine particles, which have been conventionally required for improving retention at the ink receiving layer, has decreased. Conversely, the presence of the porous inorganic fine particles decreases the sublimability of the sublimation-type textile printing ink, and becomes a factor for causing the sublimation-type textile printing ink to remain on the ink receiving layer, and thus improvement has been desired for this.
Moreover, in the case of sublimation-type inkjet textile printing transfer paper provided with an ink receiving layer containing a pigment such as silica, for example, as in the sublimation-type inkjet textile printing transfer paper disclosed in Patent Literature 1 and 2 described above, there is an advantage in that the dryability of the sublimation-type textile printing ink is good when inkjet printing is performed, but the amount of the sublimation-type textile printing ink remaining on the sublimation-type inkjet textile printing transfer paper tends to increase when transfer printing is performed onto the transfer target object. As a result, there is a problem that the transfer onto the transfer target object becomes insufficient, so that the efficiency of transfer onto the transfer target object, such as the resolution of a transferred image, the density level of the transferred image, and the uniformity of these, cannot reach the level required in recent years.